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|
assert MODE == 'CLIENT', '[nossr]'
import CanvasApp from require 'mmm.canvasapp'
import rgb from require 'mmm.color'
import article, h1, p, div, span, input, button from require 'mmm.dom'
fast = true
center = true
center_char = do
canvas = document\createElement 'canvas'
ctx = canvas\getContext '2d'
cache = {}
(char, font, height) ->
name = "#{char} #{height} #{font}"
return table.unpack cache[name] if cache[name]
ctx\resetTransform!
ctx.font = "#{height}px #{font}"
width = (ctx\measureText char).width
canvas.width, canvas.height = width, height * 1.2
ctx.font = "#{height}px #{font}"
ctx.textBaseline = 'top'
ctx.fillStyle = rgb 0, 0, 0
ctx\fillText char, 0, 0
data = ctx\getImageData 0, 0, width, height * 1.2
local xx, yy
if fast
loop = window\eval '(function(data) {
var xx = 0, yy = 0, n = 0;
for (var x = 0; x < data.width - 1; x++) {
for (var y = 0; y < data.height - 1; y++) {
var i = y * (data.width * 4) + x * 4;
var alpha = data.data[i + 3] / 255;
xx += x * alpha;
yy += y * alpha;
n += alpha;
}
}
xx /= n;
yy /= n;
return [xx, yy];
})'
res = loop nil, data
xx, yy = res[0], res[1]
else
xx, yy, n = 0, 0, 0
for x = 0, data.width - 1
for y = 0, data.height - 1
i = y * (data.width * 4) + x * 4
alpha = data.data[i + 3] / 255
xx += x * alpha
yy += y * alpha
n += alpha
xx /= n
yy /= n
cache[name] = { xx, yy, width }
xx, yy, width
class CenterOfMass extends CanvasApp
width: window.innerWidth - 20
height: 300
new: (text, @font, @size) =>
super!
@text = {}
for i = 1,#text
@add text\sub i, i
add: (char) =>
rcx, rcy, w = center_char char, @font, @size
cx, cy = w/2, @size/2
vx, vy = 0, 0
table.insert @text, {
:char, :rcx, :rcy, :w
:cx, :cy, :vx, :vy
}
refresh: =>
for char in *@text
char.rcx, char.rcy, char.w = center_char char.char, @font, @size
keydown: (key) =>
if key == "Backspace" or key == "Delete"
table.remove @text
elseif string.len(key) == 1
@add key
update: (dt) =>
super dt
ACCEL = 4 * dt
DAMPING = 8 * dt
for char in *@text
{ :rcx, :rcy, :cx, :cy, :w } = char
if not center
rcx, rcy = w/2, @size/2
dx, dy = rcx - cx, rcy - cy
char.vx += dx * ACCEL
char.vy += dy * ACCEL
char.cx += char.vx
char.cy += char.vy
char.vx *= DAMPING
char.vy *= DAMPING
draw: =>
@ctx\clearRect 0, 0, @width, @height
@ctx.font = "#{@size}px #{@font}"
@ctx.textBaseline = 'top'
x, y = @size * .1, @size
for { :char, :cx, :cy, :w } in *@text
if x + w > @width
x = 0
y += @size * 1.2
@ctx\fillText char, x + w/2 - cx, y - cy
x += w
_content = {}
append = (x) -> table.insert _content, x
append h1 'Fonts aligned by Center-of-Mass'
app = CenterOfMass "Click here and type Away!", "Times New Roman", 40
append app.canvas
app.canvas.style.backgroundColor = '#eee'
add = =>
append div {
span 'font: ',
with @font_input = input!
.type = 'text'
.value = 'Times New Roman'
with button 'set'
.onclick = (_, e) ->
app.font = @font_input.value
app\refresh!
}
append div {
span 'size: ',
input type: 'range', min: 2, max: 120, value: 40, onchange: (_, e) ->
size = e.target.value
@size_label.innerText = size
app.size = size
app\refresh!
with @size_label = span '40'
''
}
append div {
span 'center characters by weight: ',
input type: 'checkbox', checked: center, onchange: (_, e) ->
center = e.target.checked
}
append div {
span 'optimize inner loop: ',
input type: 'checkbox', checked: fast, onchange: (_, e) ->
fast = e.target.checked
}
add {}
article _content
|
